1. Field of the Invention
This invention relates to an electrochemically active alloy of aluminum in which the alloy has selected inclusions of elements, which improve the alloy for utilizing it in special circumstances, such as corrosion protection and primary elements.
2. Description of the Prior Art
It is generally known that electrodes, preferably for use as primary elements, are essentially made from zinc. However, due to the high price of zinc, they are not cheap enough. Hence, there is a tendency to try and discover a material which would have the same properties as zinc, or even better, but which would be cheaper.
It has been considered and tried to put into use aluminum dipped in the electrolytic solution that represents in principle a useful system for practical application as an electrode for the primary elements or for protection against corrosion. It has a high negative theoretical equilibrium potential and high ampere/hour capacity since each atom exchanges 3 electrons in the process of ionization. In practice, however, aluminum cannot be used as a pure metal since, due to the formation of a protective oxide layer, the open-circuit potential spontaneously establishes at a far more positive value than the theoretical one. If the potential is made more positive than the open-circuit potential in order to dissolve aluminum anodically, passivization of its surface very soon occurs and the process of dissolving either slows down considerably or stops. Besides, contrary to expectations, hydrogen evolution reaction with the corresponding self-corrosion of aluminum is enhanced at more positive potentials (the so-called "negative differential effect").